The shooting of a U.S. congressman this summer by a man described as “always angry” reminded Americans that while anger is a biological necessity, it can rapidly morph from a life-preserving force to a deadly one.

Unrestrained anger causes some to murder people they profess to love, such as the Draper man who shot Memorez Rackley and her son. It compels people to set police cars on fire, to chase drivers who accidentally cut them off in traffic, and to pelt store clerks with avocados. It causes politicians to body slam reporters, as happened in Montana in May.

And it’s anger, not religion or politics, that is the root cause of terrorism across the globe, says one neuroscientist who has studied why anger causes people to become violent.

“It’s a huge problem, and it’s a growing problem,” said R. Douglas Fields of Bethesda, Maryland, author of “Why We Snap, Understanding the Rage Circuit in Your Brain.”

In a survey conducted by Esquire and NBC News last year, roughly half of Americans said they’re angrier than they used to be, and nearly 7 out of 10 said they’re angered by something in the news at least once a day. The National Institutes of Health says more than 16 million Americans have a condition called intermittent explosive disorder, in which people get angry out of proportion with the circumstance…

Why we get angry

Anger begins with a threat, real or imagined, that is detected by a part of the brain called the amygdala. Only about a half-inch long, the amygdala is on high alert even when we’re busy or distracted, and it’s so sensitive that even a picture of person who is frowning can set off a chain of reactions designed to protect us and our families from harm.

Adrenalin, cortisol and testosterone flood the body, giving us energy and focus, and fueling aggression. Blood races through the body, our breathing grows shallow and fast, and our heart pounds, preparing us for a fight. Even our facial expressions — narrowed eyes and a scowl — warn other people to back off.

The rapid-fire impulse to react to serious threats is what enabled human beings to survive in ancient times, said Fields, the neuroscientist in Maryland.

Does a Rage Room Work?

…if you’re struggling with anger issues of your own, stay away from other angry people, particularly on the internet. One 2013 study found that people who read online rants for five minutes became angrier themselves.

For anger that has another underlying cause, such as depression, a class of drugs known as selective serotonin reuptake inhibitor (such as Prozac) can help, as does cognitive behavioral therapy, Potegal said.

If all fails, try an anger room, which is safe, and if nothing else, entertaining. At Tantrums in Houston, Baker will custom-design a room with images of things, or even people, who make you mad. In November, she prepared one room with mannequins that looked like candidates Hillary Clinton and Trump. Everything was smashed by the time the customer left the room.

Well, we’ve got a Rage Room coming soon in Tempe. It’ll be a fun place where you can let go and smash your frustrations away.

However, not all anger issues can be fixed in a Rage Room. With that in mind, we’ve complied a list of local Phoenix Area Stress and Anger Management Therapists. The list is not conclusive, it’s random, and we don’t endorse any one on it, nor are we affiliated with any of them. If you’d like to be added to the list, please provide the name of your clinic and website in the comments below.